Polyarylene sulfide ketones are excellent in chemical resistance, acid resistance, alakli resistance, dimensional stability and mechanical properties, variety of uses have been investigated, for example, as engineering plastics, fibers, films, matrices for composite materials and/or the like.
For example, a poly(arylene sulfide ketone) obtained from 4,4'-difluorobenzophenone and sodium sulfide is disclosed in Journal of Polymer Science: part A, 27, 661-669 (1989).
Further, a poly(arylene sulfide ketone) obtained from 1,4-bis(4-fluorobenzoyl)benzene and sodium sulfide is described in DE-OS 3,405,523.
Those poly(arylene sulfide ketone)s, however, require improvements in heat resistance and moldability.
For example, U.S. Pat. No. 4,870,153 discloses a poly(arylene ether ketone) from 4,4'-bis(p-fluorobenzoyl)naphthalene and hydroquinone.
Further, EP 0428743 describes poly(arylene ether ketone)s, and fibers and films made therefrom.
Those poly(arylene ether ketone)s have excellent characteristics as stated above, but a further improvement of heat resistance is required. Also, chlorides cannot be used as a starting substance because polymerizability is low and gelling frequently occurs during polymerization. Thus only fluorides have been employed, however, they are expensive.